A bit on how to test your glow plugs

This should work with any diesel engine...

Category:

Autos & Vehicles

Tags:

• glow
• plugs
• not
• working
• dead
• test
• testing
• help
• diesel
• 7.3L
• 6.9L
• idi

[Alexamstel]

This is NOT the way to test a glow plug, a BAD glow plug can give no resistance!!

The way to check it (and to make sure!!), is by using electrical wire (connected to the battery positive, red) and look for a spark when you touch the nut of the glow plug when it is screwed into place. Be carefull not to touch the other metal parts and only touch the nut of the glow plug shortly.

no spark = bad and replace.

spark = good (enough).

[blackhawk8427]

@Alexamstel Actually, this IS the way, I've been TRAINED as a diesel mechanic. Although you should use a digital meter, since the true reading should be about 3ohms. You are correct however, about NO resistance (I stated that wrong), that indicates a bad plug, you want SOME/LITTLE resistance. Your way of testing may work sometimes, but isn't a good way to test them, as a plug with NO resistance would SPARK! Think of it as a short - shorts will spark, just jumper across bat terminals!

[mchl8]

i have 2 questions for u? what about a weak reading? does that work or not so good? and now an injector question: i have an injector that will not stop leaking on the return side changed the o rings and umberilas for that bank. no loss of power nor any smoke reveiling signs of a weak cyl. what is next to stop the leak?

[blackhawk8427]

@mchl8 lots of silicone and duct tape :P jk, are u sure its the o-rings and not the hose(s)? and that the o-rings are the right size? and that the cap isnt cracked (happens easy)? how bads the leak?

[100lilabner]

@100lilabner to make the first craking and explosion easier to start the motor, with out glow plugs a diesel pick up would most likely NOT START in weather below -5C and colder. below freezing.

[100lilabner]

@emoskater1212 a glow plug is what all diesel motors use to start the motor. unlike a car a diesel does not have spark plugs, the diesel motor compress the fuel and air mix so much that it becomes hot and explodes. thus creating crank power in a diesel, where as a gas motor compresses not so much and has a aprk to ignight the fuel air mix, no to answer the glow plug question. when you go to start a diesel the glow plugs will turn on for 5-15 secs to pre warm the air in the motor

[emoskater1212]

whats a glow plug

[blackhawk8427]

@mattlock666 oops yea haha amps is flow :P

[mattlock666]

@blackhawk8427 ohms is a mrasure of continuity, not flow.

[tom58c]

@MrBlaze001 Its ok man, I figured this out a long time ago. I did all my videos of getting my truck running.